1. Field of the Invention
The present invention relates to a swing type multi-way switch of illuminated type that has a light source built therein for illuminating an operation knob or button of the switch.
2. Description of the Related Art
For example, in mobile phones, digital cameras, PDAs (Personal Digital Assistances), car navigation systems, various types of audio-visual equipments or apparatuses and their remote controllers, etc., there is used a swing type multi-way switch in which an operation knob or button thereof can be tilted in plural directions or ways. In general, a multi-way switch comprises an operation knob, and a plurality of switch elements disposed on the periphery of the operation knob and in predetermined plural radial directions therefrom, and it is arranged such that in case of selecting a desired specific function, the operation knob is tilted in one direction of the predetermined plural directions in which the switch elements are disposed to actuate (turn on or off) the corresponding one switch element, thereby to select the desired function.
One example of the swing type multi-way switch is disclosed in Japanese Patent Application Public Disclosure No. 264074/1996 (08-264074) and Japanese Patent Application Public Disclosure No. 329789/1996 (08-329789). This swing type multi-way switch is constructed such that four switch elements thereof are disposed on the periphery of an operation knob thereof and in four radial directions therefrom, one being in the upper side direction, the second being in the lower side direction, the third being in the left side direction, and the fourth being in the right side direction, and one of four functions can be selected by tilting the operation knob in one direction of the upper side, lower side, left side and right side directions and actuating the corresponding one switch element. In addition, one example of the swing type multi-way switch that is also capable of using as a pointing device is disclosed in Japanese Patent Application Public Disclosure No. 50178/1998 (10-050178).
Each of the swing type multi-way switches disclosed in Japanese Patent Application Public Disclosure No. 264074/1996 and Japanese Patent Application Public Disclosure No. 329789/1996 is a four way switch that comprises an operation knob (operation key) and four switch elements (tact or tactile switches), and four operation parts for moving a blinking or winking cursor in the upper side, lower side, left side, and right side directions respectively are formed integrally with the operation key on the upper side, lower side, left side, and right side of the top surface thereof. It is constructed that by depressing one of the four operation parts of the operation key, the operation key is caused to be slanted in one direction of the upper side, lower side, left side, and right side directions to actuate the corresponding one tactile switch, thereby to select a desired specific function. Each of the swing type multi-way switches disclosed in these Japanese Patent Application Public Disclosures is a multi-function switch that is used in an audio-visual equipment installed mainly in a house or home such as an audio system, and its features reside in elimination of incompatibility in operation, reduction of manufacturing cost, and the like. Accordingly, it is clear that in these inventions, there is entirely no technical concept that the operation key (operation knob) should be illuminated. Of course, these Japanese Patent Application Public Disclosures neither disclose nor suggest that the operation key should be illuminated.
The multi-way switch disclosed in Japanese Patent Application Public Disclosure No. 50178/1998 includes an operation shaft, an operation knob mounted on the outer end of the operation shaft, and four switch elements (pressure-actuated switches), and the operation shaft is constructed such that it can be tilted in any directions, be moved in its axial direction by depression thereof, and be rotated about its axis. It is constructed that when the operation knob is tilted in either one direction of the front side, rear side, left side, and right side directions, the corresponding one pressure-actuated switch can be actuated, when the operation knob is depressed, a pressure-actuated switch mounted on a rotary switch of the multi-way switch can be actuated, and when the operation knob is rotated, the rotary switch can be actuated. This multi-way switch is a multi-function switch that is used in, for example, a car navigation system mounted to an automobile, and the operation shaft and the operation knob are mounted on the central portion of the multi-way switch. Moreover, since the multi-way switch has its upper swinging dome mounted thereon, there is entirely no technical concept that the operation knob should be illuminated. Of course, this Japanese Patent Application Public Disclosure neither discloses nor suggests that the operation knob should be illuminated.
Recently, there has been developed a swing type multi-way switch of illuminated type that has an internal light source built therein for illuminating an operation knob or button of the switch as a swing type multi-way switch used in a small-sized or miniature portable electronic apparatus or equipment such as a mobile phone, digital camera, PDA, and the like, in order to make easy the function selecting operation or action of the multi-way switch as well as to make it possible to carry out the function selecting operation of the multi-way switch with ease even in a dim or dark place. A proposed illuminated type multi-way switch is generally constructed such that a light source is disposed under the swinging mechanism thereof and the operation knob or button is illuminated by irradiating it with light from the underside thereof.
However, in a prior art non-illuminated swing type multi-way switch, if a light source is disposed under the swinging mechanism thereof, there occurs a problem that light irradiated from the light source is obstructed by a potion of components that constitute the swinging mechanism so that the light does not reach sufficiently all over the rear surface of the operation knob. Moreover, there is also a problem that the light irradiated from the light source that is disposed under the swinging mechanism leaks from the periphery of the operation knob, which results in bad external appearance of the whole of the multi-way switch.
It is an object of the present invention to provide a swing type multi-way switch of illuminated type that is constructed such that light irradiated from a light source that is built in the multi-way switch reaches substantially all over the rear surface of an operation knob or button without being obstructed.
It is another object of the present invention to provide a swing type multi-way switch of illuminated type in which a light source built in the multi-way switch is surrounded in its periphery by a square or rectangular tube-like member and a square or rectangular frame-like holder that is fitted in the upper side of the exterior wall of the square or rectangular tube-like member and light irradiated from the light source is prevented from leaking to the outside of the operation knob or button.
In order to accomplish the above objects, in an aspect of the present invention, there is provided a swing type multi-way switch that comprises: a box-like operation knob the top of which is closed and the bottom of which is open; a square frame-shaped holder that is disposed in the inside of the operation knob and rotatably supports the operation knob; a case that has an outer square tube-like member and an inner square tube-like member coaxially formed, and rotatably supports the holder by a second axis for rotating movement orthogonal to the axis for rotating movement of the operation knob, the side wall of the operation knob and the side wall of the holder being disposed in a groove that is formed between the outer square tube-like member and the inner square tube-like member; a base plate on which a light source and a plurality of switch elements are to be mounted, and that supports the case, the light source and the plurality of switch elements being disposed and mounted on the base plate such that when the base plate supports the case, the light source is located on substantially the central portion of the inner square tube-like member of the case as well as the plurality of switch elements are located on the outside of the inner square tube-like member of the case.
In a preferred embodiment, the operation knob is formed into a box-like shape of a generally square in plan, a pair of side walls opposed to each other has projections or tongues that are formed integrally therewith and hang down respectively from the lower ends of substantially the same positions of the central portions thereof, and another pair of side walls opposed to each other has fitting holes formed at substantially the same positions of the central portions thereof, these fitting holes being aligned with a straight line passing through the center of the operation knob and each fitting hole passing through the corresponding side wall.
The holder has a shape of a generally square in plan, a pair of frame components opposed to each other has fitting holes formed at substantially the same positions of the central portions thereof, these fitting holes being aligned with a straight line passing through the center of the holder and each fitting hole passing through the corresponding frame component, and another pair of frame components opposed to each other has support axes for the operation knob formed integrally therewith at substantially the same positions of the central portions thereof, each operation knob support axis fitting in the corresponding one of the fitting holes of the operation knob and projecting outwardly, the aforesaid another pair of frame components further having projections or tongues that are formed integrally therewith and hang down respectively from the lower ends of substantially the same positions of the central portions thereof.
The outer square tube-like member and the inner square tube-like member of the case have shapes of a generally square in plan respectively, the bottom of the outer square tube-like member is coupled to and integrally with the outside wall of the inner square tube-like member by use of a coupling flange at a predetermined height position of the inner square tube-like member from the bottom thereof, and a pair of side walls opposed to each other of the inner square tube-like member has support axes for the holder formed integrally therewith at substantially the same positions of the central portions thereof, each holder support axis fitting in the corresponding one of the fitting holes of the holder and projecting outwardly. The coupling flange has openings formed therein through which the pair of projections of the operation knob and the projections of the holder pass through with a play or gap therebetween, respectively. Both the holder and the case are made of a light opaque material.
The base plate has a shape of a generally square in plan, the light source is disposed on the central portion of the top surface of the base plate, first and third switch elements are aligned with one centerline passing through the light source and disposed on locations where distances from the light source are substantially the same with each other, second and fourth switch elements are aligned with a second centerline orthogonal to said centerline and disposed on locations where distances from the light source are substantially the same with each other, and these switch elements are selectively turned on/off by the pair of projections of the operation knob and the pair of projections of the holder.
With the construction as described above, a light source built in the multi-way switch is surrounded by the inside wall surface of the inner square tube-like member of the case and the inside wall surface of the frame-like holder that is fitted on the outside wall surface of the inner square tube-like member. In addition, the upper portion and the side walls of the frame-like holder are covered by the box-shaped operation knob, and the side walls of the operation knob as well as the side walls of the holder are accommodated in a groove that is formed between the outer square tube-like member and the inner square tube-like member of the case. As a result, the light source lies in the condition that any light from the outside is perfectly shut out. Accordingly, light emitted from the light source does not leak from the periphery of the operation knob.
In addition, since the top of the inner square tube-like member and the top of the holder are open, any member or element obstructing light does not exist at all between the light source and the rear surface of the top wall of the operation knob. Accordingly, light emitted from the light source reaches the rear surface of the top wall of the operation knob substantially without being obstructed so that it can sufficiently and substantially uniformly illuminate almost all over the rear surface of the operation knob.